1. Field of the Invention
The present invention relates to a substrate processing method, a substrate processing system, and a computer-readable storage medium.
2. Description of the Related Art
In a process of manufacturing a semiconductor device, for example, patterning is performed for forming a predetermined pattern in a specific film to be processed above a wafer. In the patterning of the film to be processed, for example, a resist coating treatment of applying a resist solution to the top of the film to be processed above the wafer to form a resist film, exposure processing of applying light in a predetermined pattern to the resist film above the wafer surface to expose the resist film, heating processing of heating the wafer to accelerate the chemical reaction in the exposed resist film (post-exposure baking), developing treatment of developing the heated resist film and so on are performed in sequence using the photolithography technique, whereby a predetermined resist pattern is formed in the resist film above the wafer surface. Thereafter, the film to be processed is etched, for example, using the resist pattern as a mask, and the resist pattern is then removed, whereby a predetermined pattern is formed in the film to be processed.
To form a finer pattern to further miniaturize the semiconductor device, conventionally the wavelength of light for use in the exposure processing in the above-described patterning has been increasingly reduced. Only by the method of increasingly reducing the wavelength for exposure, however, it is difficult to form a fine semiconductor device at a level of, for example, 32 nm or 45 nm. Hence, it is proposed to perform a plurality of rounds of patterning, for example, on the film to be processed at the same layer above the wafer surface to form a finer pattern, so as to miniaturize the semiconductor device (Japanese Patent Application Laid-open No. H7-147219).
If a second round of patterning is started to form a resist film above the surface of the wafer, for example, immediately after a first round of patterning is completed, the resist film may not be formed flat due to projections and depressions of the pattern in the first round above the surface of the wafer. If the resist film is not formed flat as described above, a poor condition may occur, such as deviation of focus of exposure during subsequent exposure processing. Therefore, it is desirable to form a film for flattening (hereinafter, referred to as a “planarizing film”) the surface of the substrate after the preceding round of patterning is completed and before the subsequent round of patterning is started.